Cyanobacteria

Phylum of photosynthesising prokaryotes

Cyanobacteria ( sy-AN-oh-bak-TEER-ee-ə) are a group of autotrophic gram-negative bacteria of the phylum Cyanobacteriota that can obtain biological energy via oxygenic photosynthesis. Cyanobacteria originated in a freshwater or terrestrial environment, and first appeared in the middle Archean eon. They are probably the most numerous taxon to have ever existed on Earth.

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